L3 Network & Security Operations Engineer

Company: Marsh Description: We are seeking a talented individual to join our   Network and Security Operations   team, part of Marsh. This role will be based in   Cluj-Napoca . This is a   hybrid   role that has a requirement of working at least   three days a week in the office . As L3 Network & Security Operations Engineer you will act as a senior escalation point for complex network incidents and changes.

This is an operational, delivery-focused role (troubleshooting, remediation, and implementation) with a strong emphasis on modern load balancing (F5 Distributed Cloud and AWS ALB/NLB), plus WAN and branch connectivity. You will join a combined Network and Security Operations team that supports end-to-end user-to-application flows across the network and security control path. The position is primarily network-operations focused, with clear exposure and progression into security operations toolsets if desired.

Working pattern Hybrid working model with an expectation of time in the office and time working from home Standard business hours, Monday to Friday Global follow-the-sun support model across EMEA, APAC, and the Americas, with structured handovers between regions Weekend on-call rota for major incidents only; shared across the full team with each person covering one weekend per rotation cycle We will count on you to: Provide   L3 escalation support   for major incidents, leading technical triage, restoration activities, and clear stakeholder communication Operate, troubleshoot, and implement   load balancing services , with a primary focus on   F5 Distributed Cloud (XC)   and   AWS Elastic Load Balancing (ALB/NLB) Manage   TLS/SSL enablement   across load balancers and, where required, firewalls/WAFs, including certificate installation, chain management, binding, renewal, rotation, and end-to-end validation Support   SD-WAN, WAN, and branch connectivity   services, including troubleshooting routing, pathing, carrier issues, and branch LAN/WLAN environments Deliver network changes safely and effectively through   ITIL-aligned governance , including planning, risk assessment, validation, and rollback readiness Produce high-quality operational documentation, ITSM updates, and closure notes to improve repeatability and reduce mean time to resolution Support legacy   F5 BIG-IP   services as required during transition to cloud/distributed platforms Contribute to the team’s broader operational capability, with opportunities to gain exposure to firewall, WAF, cloud security controls, Zero Trust, and microsegmentation technologies Growth & development (security operations pathway) Opportunity to develop hands-on experience with firewall and WAF implementations where traffic flows require termination/inspection and policy troubleshooting Exposure to cloud security controls and segmentation (e.g., security groups and cloud-native access patterns) as part of end-to-end flow support Option to broaden into Zero Trust and microsegmentation technologies used by the team (e.g., Zscaler, Elisity, Illumio), depending on interest and team needs What you need to have: Proven   L3 Network Operations   experience as a senior escalation resource in a   NOC/operations   environment.

Strong troubleshooting capability across   L2–L7 , including   TCP/TLS and HTTP/HTTPS , with a structured and methodical approach to fault isolation and remediation Hands-on experience with   cloud/distributed load balancing , including   F5 Distributed Cloud and/or AWS ALB/NLB Practical experience deploying and managing   CA-provided certificates , including import/install, chain management, binding/configuration, renewal/rotation, and post-change validation Solid experience with   Cisco multilayer switching   (Layer 2 / Layer 3), including configuration and troubleshooting of VLANs, SVIs, routing, and high-availability concepts Solid experience troubleshooting   WAN and branch connectivity , including working with carriers and vendors during outages Stron